Green treatments for polyaromatic hydrocarbons in e-wastes

Rapid elevation of global population along with increased urbanization and industrialization afflict the water resources leading to the blooming of wastewater. Two or more aromatic rings fused with organic compound Polycyclic Aromatic Hydrocarbons (PAHs) emerged worldwide through anthropogenic processes, mainly due to the incomplete combustion of organic fuels. In accordance with the United States Environmental Protection Agency (USEPA), there are 16 PAHs that are deemed as primary pollutants. These are toxic to the living organisms due to their pervasive existence, rebelliousness, potential for bioaccumulation and carcinogenic venture. Several methods including fixation, incineration and oxidation are put forward to remove PAHs. Occasionally some fictional toxic products are produced by the incomplete removal of PAHs. Bioremediation is one of the ecological techniques to remove the PAHs. Microbial biodegradation is considered as an effective and inexpensive technique to remove PAHs along with other hydrocarbons and xenobiotic compounds and are accomplished by few PAHs degrading bacteria including Haemophilus spp., Mycobacterium spp., Paenibacillus spp., Pseudomonas aeruginosa, P. fluorescens, Rhodococcus spp. along with few biosurfactant-producing microbes. The novel biochemical events involved in hydrocarbon catabolism are microbial physical adaptation, their acquisition and uptake. The bioremediation efficacy can be further ameliorated through genetic modification of the microbes. This chapter will focus on the eco-friendly treatment for the PAHs remediation in in situ and ex situ. This chapter will explore the remediation of the PAH by-products through the multi-process conjunctional treatment processes under the green therapy.